# Emergence of world-stock-market network

## TL;DR

This paper investigates the collective behavior of forty influential global stock markets using cross-correlation analysis and Random Matrix Theory, revealing a structured world-stock-market network with geographically clustered communities.

## Contribution

It introduces a novel analysis of global stock market dependencies, identifying a structured network and community formations based on correlation data.

## Key findings

- Markets exhibit significant collective behavior.
- The world market forms three geographically-based communities.
- The analysis supports the concept of a unified global financial market.

## Abstract

In the age of globalization, it is natural that the stock market of each country is not independent form the other markets. In this case, collective behavior could be emerged form their dependency together. This article studies the collective behavior of a set of forty influential markets in the world economy with the aim of exploring a global financial structure that could be called world-stock-market network. Towards this end, we analyze the cross-correlation matrix of the indices of these forty markets using Random Matrix Theory (RMT). We find the degree of collective behavior among the markets and the share of each market in their structural formation. This finding together with the results obtained from the same calculation on four stock markets reinforce the idea of a world financial market. Finally, we draw the dendrogram of the cross-correlation matrix to make communities in this abstract global market visible. The dendrogram, drawn by at least thirty percent of correlation, shows that the world financial market comprises three communities each of which includes stock markets with geographical proximity.